HyperspectralImaging
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Researchers turn a DSLR into hyperspectral camera using PVC and duct tape, MacGyver green with envy
Hyperspectral imaging is a method that captures a far greater amount of the electromagnetic spectrum than a regular photograph. This makes it ideal for a variety of uses, from night vision to identifying mineral deposits from afar, but the problem is that hyperspectral sensors don't come cheap. However, some intrepid imaging scientists have come up with a way to turn your DSLR into a hyperspectral camera using stock SLR glass, a gel diffraction filter, PVC pipe, duct tape, some serious ingenuity and plenty of elbow grease. Thusly did they build a (relatively) cheap-as-chips imaging spectrometer that can deliver spectral resolution equal to that of commercial solutions at a far lower cost. The result of their labor is a computed tomography image spectrometer (CTIS), which takes hyperspectral images by splitting light into spectral bands with a diffuser and recording them using a Canon EOS 5D Mark I in HDR mode. As constructed, the prototype takes a spectral resolution of up to 4.89nm in a 120 x 120 pixel area, though at a longer exposure time than dedicated devices. Having proven their concept, the plan is to build another lens extension using custom tubes and lenses that'll both reduce weight and increase the aperture to shorten the exposure time -- all for less than a grand. You can see both the camera's construction and some sample images in the gallery below, plus you can dig deep into the nitty gritty behind this bit of imaging black magic at the source link. %Gallery-141944%
Hyperspectral imaging reveals Declaration of Independence rough draft dubbed citizens 'subjects'
Imagine, if you will, Thomas Jefferson sitting down to pen (or quill) a rough draft of the Declaration of Independence early in 1776... you know, when the colonies that would become the United States of America formally explained their decision to become independent states, and thus not be a part of Great Britain any longer. Imagine him writing the words "our fellow citizens" -- but know that, thanks to hyperspectral imaging, the Library of Congress has confirmed that he originally wrote "our fellow subjects" -- but then scrubbed it out and replaced it with the word "citizens." Personally, we feel pretty happy with the knowledge that the founding fathers chose their words so carefully -- after all, "we hold this stuff to be super obvious 'cause all dudes are like, basically the same" just doesn't have the same ring to it, now does it? Hit up the Boing Boing source link for far more photos.
